Americans are putting more solar panels on their roofs than ever before. Yet only a small group of people — homeowners, mostly well-to-do — are driving the boom. Apartment dwellers, cash-strapped families, renters and others are largely shut out of the solar movement, sidelined by financial and technical constraints.

Enter community solar projects.

Paul Hyun and his neighbors have one of them on their rooftop. They live in a 70-unit apartment complex in a tightly packed neighborhood in the Brooklyn borough of New York. A solar array is affixed to the roof, and each neighbor pays about $80 a month to cover the cost of installing and maintaining the system. All the electricity that’s produced is sold to the local utility, Consolidated Edison Inc., and the neighbors split the proceeds.

Hyun said he typically saves 15 to 30 percent on his electric bills thanks to the solar panels. In January, he received a $1,000 rebate check from the housing cooperative, which manages the project.

“When I talk to my neighbors in other buildings, a lot of them are jealous of what we have,” said Hyun, a real-estate agent in Sunset Park.

Shared solar arrays are a tiny but growing segment of the broader U.S. solar market. As demand for cleaner and cheaper energy rises, more residents are finding alternative ways to access renewable energy — even when they don’t own homes or have deep pockets.

Such projects are critical for accelerating the nation’s overall use of lower-carbon energy, analysts say. More than three-quarters of U.S. homeowners can’t put up panels because their roofs are positioned wrong or the costs are too high. Even fewer renters, public-housing residents or condo owners can go solar due to building restrictions.